Printing-telegraph-exchange system



Nov. 15', 1927., I 1,648,975

' a. s. VERNAM PRINTING TELEGRAPH EXCHANGE SYSTEM .Filed March 18. 1926 q r\ Pstented Nov. l5, lQZZ,

nears srnrss r ars GILBERT S. VEENAM, OF RIVER EDGE, NEW JERSEY, A$SIGNOR T AMERICAN WILE- ZPHONE AND TELEPGRAPH COMPANY, A CORPQRATION OF NEW 'YZQRK.

PRINEING 'l'ELEGRAPE-EXGHANGE EEYSTEM.

Application filed March 18, 1926. Serial No. 95,728.

This invention relates to telegraph systerns, and particularly to those wherein the local power supply at printing stations is controlled from a distant point.

An object of this invention is to efi'ect a saving in current consumption and to reduce the maintenance expense of telegraph sys terns Another object is to automatically render effective a receiving set when the same 15 re aired for use and to disable it when no ion zer required In accordance with this invention the mo; tors interconnected stations are arranged to be controlled from' the station originating the connection, and in this arrangement the motors are started by the momentary operation of the switching means at the orig1- mating station and are stopped by the prolonged operation of the same means; Ac ccrclingly a feature relates to the employment at each of the interconnected stations of a slow-acting condenser in which a cliecurrent thereirom need as a means for effecting the stopping the rnotors, the condenser at the originating station requirin a longer period for charging than that at the terminating station, thereby insuring a sufficient charge to accumulated in the condenser the latter s ation before a similair charge is store" at tle ormer, together keys at the stations controlling the g'injc' of said condensers. I r .e above and other objects and features his invention are set forth in the i'i'olo ring description appended clainns and may he more readily understood when the description is taken in conjunction with the acccinbanying which. illustrates the invention.

in the drawing there is shown a telegraph. pr' sting system consisting of a central otiice and two subscribers stations with only that apparatus necessary for clear understanding the invention. Referring now to the drawing, there are shown two printing telegraph subscribers stations A and B interconnected through a central office C. it will be understood oi? course, that in actual practice many other lines similar to that shown may mina'te at the same central otiice and oft lv that interconnections may be established.

otlice by eit er manually or automaticaiiy cgaerated means it will also be under' stood that invention will. not be con.

fined to only those systems employing central switching stations but may also be adapted to such systems as those in which the subscribers stations are interconnected by direct, or fixed, lines, or in which the subscribers stations are arranged radially in respect to a central point from which point the motors at the subscribers stations may be controlled,

Assume for the purpose of illustration that the subscriber desires to communicate telegraphically with the subscriber B that the connection is established through central cfice C. The subscribe would there. upon transmit a start signal actual a non-loclring hey l. the line circuit corn" prising" wires i arid 5i and extending thrcngh central ofiice {l to the subscribers station id, is momentarily opened However, this open period efiected in the line circuit by the hey i is longer than the periods ordinarily effected by message signals. The opening of the line circuit causes a deenergization of line relay which releases at reby at ture a circuit extending trons. ground, through the winding oi lay 6,, tarough the printer magnet 7,, to batter Relay 6 releases, at its lov. armature and back contact connects groi iii to a circuit enth ing through. the winding oi relay 8, to bat terry at the 'ri ht armature of relay 9 Relay 8 operates and nice s a locking circuit itself at its ieft armature.

The subsequent closing of when key 1 is releas T-GTITIZQS which operates and c ects circuit extending; through the winds o lay 6; Relay re-energizes and thereby ,ral operating circuit of relay 8 and closes an operating; circuit for relay 10, the latter circuit being" tracec le from battery at right armature oi relay it, through the winding of relay 10 right ai ma ture of relay 8, to ground at the lower arms ture of relay 6. ltelay it) operates and closes at its left armature a locking circu for itself and at its right armature circi for starting," motor Lil,

fi imultaneously with the de energizaticn and re-energization of relay 3 when the l. at station is momentarily operated, relay 3 at the di tant station is tie-energized and re ener ed similar manner, and motor 11 1S correspondingly operated conjunction with relays 8" and 10 as de- Quill lie;

was.

scribed for the motor ill at the originating, or transmitting, station A.

subscriber at station A, ai'ter releas ing the non-locking key 1 to permit the clos ing of the line circuit, operates his transmittor for transmitting to station B the innulses which constitute the message. During the transmission of the message impulses the line circuit is opened and closed in rapid succession at the transmitter 2 of the send :ing station and relays 3 and 3, respectively, at stations A and B, (lo-energize and reenergize accordingly, to effect the recording operation of the printer magnets 7 and 7, respectively, at stations A and B. A record of the transmitted message is therefore made at both stations A and B.

At the end oi each message impulse when relay 3 releases, relay 6 and magnet 7 like- Wise release but the release of these relays at this time has no eilect on relays 8 and 10 which are maintained in an operated condition by their respective locking circuits, as hereinhelfore mentioned. Should the subscriber at the distant station 18 desire to send a break signal to station A, he will operate key 1" momentarily to open the line and the consequent release oi relays 3 and 6 and magnet 'i station A will likewise have no eil'ect on relays 8 and 10. Relay 6, Which. operates and releases with line relay 3, may, ii desired, he designed to he slightly slow-torelease so that it will .i,i./...-JE)UHCl only to the longer interruptions clue to the operation of hey i at the distant station for the purpose I of sending a lorcak signal.

' V hen relay 6 releases in response to either the message impulses or break signals, the condenser 18 charges through the high resistance 122 in a circuit which may be traced from battery, condenser 13, upper armature hack contact of relay 6, left contact oi lrey l, resistance 12, to ground at the left armature oi relay id. The resistance 12 is Oil such value that condenser i3 will ceive only a very slight charge during these short lorealrs of the line circuit, and therefore these charges produce no eiiect when re lay d re-energizes and the condenser is permitted to be discharged through the low resistance Winding of relay 9, as will hereina'fter he explained.

At the completion. of the message, the subscriloer at station-1i. again actuates hey i to stop the root-ore at stations A and 1B but at this time the hey is held in open posi-- tion for an interval. longerihan that required for starring the motor 10 to 29 seconds. A circuit is thereby closed from hattery, condenser 18, high resistances ll and in series, to aund at the left arms-- ture l0. circuit, which is closed the long interval, condenser 13 receive a charge approximately equivalent,

s to the full "voltage of the battery,-

when

cuit for the long the. key 1 is released, relay 6 operates and closes a circuit from battery, through the condenser, upper armature and front contact of relay 6, through the normal contact and comparatively low resistance "winding oi relay 9, to battery. The closing oi the cirinterval permits the accumulation of a high positive charge on the right-hand plate oi. condenser 13 and when relay 6 subsequently operates, discharged through the Winding of relay 9 to the negative side oi battery and is of sufficient strength to cause relay 9 to operate. Relay 9 in operating opens its normal contact and loclrs to its left armature in a circuit extending over the right contact of relay 8, to ground at the lower armature of relay 6. Also, relay 9 opens at its right armature the locking circuits for relays 8 and 10 and these two latter relays are released. The release of relay 8 opens the locking; circuit for relay 9 and relay 9 releases. The release oii relay 10 opens the operating: circuit for motor 11 and the motor stops. The inotor 1'1 at station l? is stopped in the same manner as that described ior motor 11 at station A, except that the circuit fl'or charging the condenser 13 at station B to appraisal mately the full VOltZiEZQ of the associated battery is extended through one resistance, namely that numbered 12', instead of resistances i l and 12 in series. The reason for this diilcrence in charging the condensers at the distant station. is explained below.

When key 1 at station A. is operated for the long interval. at the completion of the message, the resistance M is included in the circuit in which condenser 13, as heretofore stated, is charged to the strength approximately equivalent to the full voltage of the battery, and at the same time the condenser 13' at the distant station B is also receiving a heavy charge inasmuch as its energizing circuit is also closed. But the circuit "for charging conde' ser 13 includes only one rosistance, namely resistance 1.2, because the other resistance, namely resistance 14,-, is shunted by a. path extending through the right contact oiv lrey 'i. The additional re sistance connected in the charging circuit for condenser 13 at station A when key it is operated "for he long interval, provides a longer period of tires for the charging of condenser l3 to approximately the lullvalue of the voltage of the hatte y than that which is required for a similar charge to be stored in condenser 13 at station This arrange nie'nt insures the stopping of all the motors d with the line circuit, when "the at the sending station Whereiroru the stop signal transmitted, is stopped.

'llhe transr ission of a message from sta-- V A he made the some described shove for stathis charge is Oil Facilities may be provided at the central ofiice for sending signals for operating the printers or controlling the motors at either station. A provision for this facility is shown on the drawing in the form of a nonlocking key 20 at office C, for opening the line comprisin wires 4 and 5.

lVhat is claimed is:

1. A communication system comprising a plurality of stations, a signal receiving set and a motor therefor at one of said stations, and means for starting and stopping the motor by transmitting impulses different in length from the signaling impulses.

2. A communication system comprising a plurality of subscribers stations, a receiving set and a motor therefor at each of said stations, and means at one of said stations for transmitting impulses to efi'ect the starting of the motors and impulses of a longer duration to effect the stopping of the motors at said stations.

3. A tele aph system comprising a plurality of su scribers stations, a printer set, a motor therefor, and a slow-acting device at each of said stations, and means for transmitting impulses of a character different from the signaling impulses to etlect the starting and stopping of the motors, the slow-acting device being responsive only to impulses of one characteristic to stop the motor.

4. A telegraph system comprising a plurality of subscribers. lines, means for interconnecting a calling and a called line, printer sets and motors for said lines, means to start said motors, and condensers serving to effect the stopping of saidmotors.

5. A telegraph system comprising a plurality of subscribers lines, means for interconnecting a calling and a called line, printer sets and motors for said lines, means to start said motors, and condensers serving to effect by their discharge action the stopping of said motors.

6. A telegraph system comprising a plurality of subscribers stations, a central office, a plurality of telegraph lines extending between said stations and said central ofiice, means at said central office for interconnecting said stations, a power supply source at each of said subscribers stations, and means at each of said stations controlled by one of two interconnected stations for effecting first the connection and then the disconnection of the sources of power at the interconnected stations, said last mentioned means at the controlling station being arranged to require a longer interval tobecome effective than the corresponding means at the other of the interconnected stations.

7. A telegraph system comprising a plurality of subscribers stations, a central office, a plurality of lines terminating at said subscribers stations, means at said central office for interconnecting a calling and a called line, a source of power at each of said stations, and means at the station of said calling line for ellecting first a connection and then a disconnection of the sources of power at the stations of the interconnected lines, said last mentioned means at the stationof the calling line being arranged to require a longer interval to become efl'ective than the corresponding means at the other of the interconnected stations.

8. A telegraph system comprising a plurality of subscribers stations, a central office, a plurality of calling and called lines terminating at each of said stations, means at said central oflice for interconnecting said calling and called lines, a motor at each of said stations, means at the station of an interconnect-ed calling line arranged to be operated momentarily to simultaneously eflect the operation of the motors at the interconnected stations, and a slow-acting device at each of said interconnected stations arranged to be inetfectively energized when the second mentioned means is momentarily operated but effectively energized when said second mentioned means is operated for a comparatively long period to stop the motors at said interconnected stations simultaneously.

9. A telegraph system comprising a plurality of subscribers stations, a central office, a plurality of calling and called lines terminating at each of said stations, means at said central oflice for interconnecting said calling and called lines, a motor at each of said stations, a key at the station of an interconnected calling line arranged to be operated momentarily to simultaneously effect the operation of the motors at the interconnected stations, and a slow-charging condenser at each of said interconnected stations'arranged to be ineflfectively energized when the key is momentarily operated but effectively energized when the key is oper ated for a comparatively long period to stop the motors at said interconnected stations simultaneously. 7

In testimony whereof, I have signed my name to this specification this 17th day of March, 1926.

GILBERT S. VERNAM. 

